I use those 4' orange electic fence stakes from home depot (about $1 a piece)for lots of things in the yard & gardens. Pound it in the ground and then slide the PVC pipe over it and into the soil a bit. Set out several of these with holes drilled in the PVC pipe and string wire through them to make a fairly sturdy, portable & cheap trellis. I use these stakes to build easy fencing. I use plastic cable ties to secure wire or plastic mesh fencing to them. Because I dislike the orange and it stands out like a sore thumb, I paint my stakes black. Pound 2 rows of these stakes in the ground about 4' apart and slide each end of a flexible PVC pipe over them, making an arch. Cover this with garden cloth or plastic to protect plants. I "sew" the fabric to the pvc with fishing line. If you are using plastic, cut some flaps in it, to keep it from blowing away in a big wind. I use them to brace non secured retaining walls. At my old house I built a raised bed using them to hold the lumber together. I drilled holes in the timbers and slid them over the stakes, then I lined the interior side with heavy plastic.

Building Science Corp.'s Dr. Joe lists vented crawlspaces as one of the top ten dumb things to do in the South--and the North. However, before attempting any changes he advises: "Be sure to consult local experts and code officials before attempting unvented attics or crawl spaces on your own."

I apologize for being dense but Iam just lobbying for people to build to code.. at the least. Prescriptive minimums are not arbitrary. They are the intent of the code. I understand and approve of alternative compliance and performance modeling as I use it on my passive solar projects to get around the fenestration requirements among other details. I also understand its limitations and how widely misused and abused that it has become. Yes, houses and climates are complex and the people who created the software are largely the ones setting the prescriptive minimums and ventilation standards. They have done a marvelous job for the most part. The software and results can be amazingly accurate in the hands of the right professional. Its the occupant behavior variable that tends to throw some things off. For example, take leaving all the windows open with the heating and cooling running.. Be careful about using software or alternative compliance paths yourself or hiring those outside of their area of expertise. Hopefully, people can identify the correct team in their area to make the appropriate choices. I hope what we've covered here will help. Bungalow14 and others who may still be considering a vented crawlspace on the East coast. The paper trail of substantiation on vented crawlspaces is immense. The level of research and evidence of poor performance with vented crawls in humid climates, mainly on the East coast, is overwhelming. The building industry is notoriously stubborn about accepting improvements to the code. I find this to be especially true with older, experienced professionals with little education in building science. Advanced Energy in Raleigh has done a lot of good research for your specific area but unfortunately, the links they used to provide on it have been taken down. I strongly suggest you talk to a building science professional in your area before building an attached cave (vented crawlspace) below your home. I imagine that you could probably get in touch with someone about this at Advanced Energy. Have you considered Energy Star or NC Green Build certification? Here is a link that might be useful: Advanced Energy website homepage

If anything, I'd think a self-test kit would yield too low of a reading, not too high. Thus, if you're at 9.1 at a self-kit, any "better" kit might be more sensitive and yield a high reading. I would think the cheaper canisters would be less sensitive. That being said, this is all my opinion, based upon zero scientific fact, for what it's worth. Also, the problems with radon readings is that they fluctuate over time, depending on a host of factors such as season, wetness of the surrounding ground, pressure in the house, windows opened/doors opened, etc. So, while a $100 inspector might come up with a different result, it might not be due to the quality of the testing, but changed conditions.